Several methods of coating preparation by reactive magnetron sputtering are known. Typically, in these methods, there is implemented a method of control which allows depositing of coatings with given amount of reactive gas in the coating. Among them are especially important coatings, when the amount of reactive gas corresponds to a stoichiometric coating. Growth rate of overstoichiometric coatings is typically significantly lower than the one of understoichiometric coatings. Understoichiometric coatings, however, are characterized by significantly worse mechanical properties. Known methods of controlling the amount of the reactive gas in a coating deposited by method of reactive sputtering can be summarized as:                In accordance with the document by A. F. Hmiel, published in J. Vac. Sci. Technol. A, 3 (1985) 592-595. a method of control by changing flow of reactive gas in dependence of the partial pressure of the reactive gas (nitrogen) is known. Quadrupole mass spectrometer was used to measure the partial pressure of nitrogen.        In accordance with document EP 0 795 623 A1 a method of control by changing flow of reactive gas in dependence on partial pressure of reactive gas (oxygen) is know. A Lambda probe was used in this document to measure the partial pressure of oxygen. I        In accordance with document Heister et al., Vacuum 59 (2000) 424-430 a method of control by changing power supplied to cathode in dependence on partial pressure of reactive gas (oxygen) is known. It is possible to measure the partial pressure of the oxygen by any sufficiently fast and precise sensor (mass spectrometer, lambda probe).        In accordance with patent document U.S. Pat. No. 4,166,784 A a method of control by changing deposition parameters (flow of reactive gas, current between cathodes) by the means of optical emission spectroscopy or voltage on discharge is known.        All above described methods of control can be successfully used for lower deposition rates and/or higher pumping speeds. It is often hard to reach sufficiently high pumping speeds to obtain high deposition rates, which makes it hard to find stable conditions for the described methods of control. The reason is significant hysteresis behavior as described by Musil et al., published in Thin Solid Films 475 (2005) 208-18 and Sproul et al., published in Thin Solid Films, 171 (1989) 171-181. Patent documents CA 1 1980 85 A1 and U.S. Pat. No. 5,492,606 A discuss this problem.        In accordance with the patent document CA 1 198 085 A1 a method of stabilization of hysteresis behavior of the system for reactive magnetron sputtering by pulsing the flow of reactive gas is known. The time (TOFF) for which the value of reactive gas flow is lower is not necessarily equal to the time (TON) for which the value of reactive gas flow is higher. These time values are recommended to be in the range of 0.2 to 0.5 s, in order to allow better deposition rates than according to the formerly published document Aronson et al., Thin Solid Films, 72 (1980) 535-540, where respective time values of TON=1.6 s, TOFF=1 s are suggested.        In accordance with the patent document U.S. Pat. No. 5,492,606 A a method of stabilization of hysteresis behavior of the system for reactive magnetron sputtering by low frequency pulsing of power applied on target is known. According to this document the recommended frequency values are 1 to 100 Hz and the recommended time values, for which the power on target is lowered, are 1 to 800 ms.        In accordance with the document by Ohsaki et al., published in Thin Solid Films 351 (1999) 57-60 a method of stabilization of hysteresis behavior of the system for reactive magnetron sputtering using sub-stoichiometric TiO2-x target. Target is produced by plasma spraying method.        